1 /*
2 * Atheros AR71xx/AR724x/AR913x MISC interrupt controller
3 *
4 * Copyright (C) 2015 Alban Bedel <albeu@free.fr>
5 * Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com>
6 * Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
7 * Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
8 *
9 * Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP
10 *
11 * This program is free software; you can redistribute it and/or modify it
12 * under the terms of the GNU General Public License version 2 as published
13 * by the Free Software Foundation.
14 */
15
16 #include <linux/irqchip.h>
17 #include <linux/irqchip/chained_irq.h>
18 #include <linux/of_address.h>
19 #include <linux/of_irq.h>
20
21 #define AR71XX_RESET_REG_MISC_INT_STATUS 0
22 #define AR71XX_RESET_REG_MISC_INT_ENABLE 4
23
24 #define ATH79_MISC_IRQ_COUNT 32
25
ath79_misc_irq_handler(struct irq_desc * desc)26 static void ath79_misc_irq_handler(struct irq_desc *desc)
27 {
28 struct irq_domain *domain = irq_desc_get_handler_data(desc);
29 struct irq_chip *chip = irq_desc_get_chip(desc);
30 void __iomem *base = domain->host_data;
31 u32 pending;
32
33 chained_irq_enter(chip, desc);
34
35 pending = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS) &
36 __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
37
38 if (!pending) {
39 spurious_interrupt();
40 chained_irq_exit(chip, desc);
41 return;
42 }
43
44 while (pending) {
45 int bit = __ffs(pending);
46
47 generic_handle_irq(irq_linear_revmap(domain, bit));
48 pending &= ~BIT(bit);
49 }
50
51 chained_irq_exit(chip, desc);
52 }
53
ar71xx_misc_irq_unmask(struct irq_data * d)54 static void ar71xx_misc_irq_unmask(struct irq_data *d)
55 {
56 void __iomem *base = irq_data_get_irq_chip_data(d);
57 unsigned int irq = d->hwirq;
58 u32 t;
59
60 t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
61 __raw_writel(t | BIT(irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
62
63 /* flush write */
64 __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
65 }
66
ar71xx_misc_irq_mask(struct irq_data * d)67 static void ar71xx_misc_irq_mask(struct irq_data *d)
68 {
69 void __iomem *base = irq_data_get_irq_chip_data(d);
70 unsigned int irq = d->hwirq;
71 u32 t;
72
73 t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
74 __raw_writel(t & ~BIT(irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
75
76 /* flush write */
77 __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
78 }
79
ar724x_misc_irq_ack(struct irq_data * d)80 static void ar724x_misc_irq_ack(struct irq_data *d)
81 {
82 void __iomem *base = irq_data_get_irq_chip_data(d);
83 unsigned int irq = d->hwirq;
84 u32 t;
85
86 t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
87 __raw_writel(t & ~BIT(irq), base + AR71XX_RESET_REG_MISC_INT_STATUS);
88
89 /* flush write */
90 __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
91 }
92
93 static struct irq_chip ath79_misc_irq_chip = {
94 .name = "MISC",
95 .irq_unmask = ar71xx_misc_irq_unmask,
96 .irq_mask = ar71xx_misc_irq_mask,
97 };
98
misc_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hw)99 static int misc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
100 {
101 irq_set_chip_and_handler(irq, &ath79_misc_irq_chip, handle_level_irq);
102 irq_set_chip_data(irq, d->host_data);
103 return 0;
104 }
105
106 static const struct irq_domain_ops misc_irq_domain_ops = {
107 .xlate = irq_domain_xlate_onecell,
108 .map = misc_map,
109 };
110
ath79_misc_intc_domain_init(struct irq_domain * domain,int irq)111 static void __init ath79_misc_intc_domain_init(
112 struct irq_domain *domain, int irq)
113 {
114 void __iomem *base = domain->host_data;
115
116 /* Disable and clear all interrupts */
117 __raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_ENABLE);
118 __raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_STATUS);
119
120 irq_set_chained_handler_and_data(irq, ath79_misc_irq_handler, domain);
121 }
122
ath79_misc_intc_of_init(struct device_node * node,struct device_node * parent)123 static int __init ath79_misc_intc_of_init(
124 struct device_node *node, struct device_node *parent)
125 {
126 struct irq_domain *domain;
127 void __iomem *base;
128 int irq;
129
130 irq = irq_of_parse_and_map(node, 0);
131 if (!irq) {
132 pr_err("Failed to get MISC IRQ\n");
133 return -EINVAL;
134 }
135
136 base = of_iomap(node, 0);
137 if (!base) {
138 pr_err("Failed to get MISC IRQ registers\n");
139 return -ENOMEM;
140 }
141
142 domain = irq_domain_add_linear(node, ATH79_MISC_IRQ_COUNT,
143 &misc_irq_domain_ops, base);
144 if (!domain) {
145 pr_err("Failed to add MISC irqdomain\n");
146 return -EINVAL;
147 }
148
149 ath79_misc_intc_domain_init(domain, irq);
150 return 0;
151 }
152
ar7100_misc_intc_of_init(struct device_node * node,struct device_node * parent)153 static int __init ar7100_misc_intc_of_init(
154 struct device_node *node, struct device_node *parent)
155 {
156 ath79_misc_irq_chip.irq_mask_ack = ar71xx_misc_irq_mask;
157 return ath79_misc_intc_of_init(node, parent);
158 }
159
160 IRQCHIP_DECLARE(ar7100_misc_intc, "qca,ar7100-misc-intc",
161 ar7100_misc_intc_of_init);
162
ar7240_misc_intc_of_init(struct device_node * node,struct device_node * parent)163 static int __init ar7240_misc_intc_of_init(
164 struct device_node *node, struct device_node *parent)
165 {
166 ath79_misc_irq_chip.irq_ack = ar724x_misc_irq_ack;
167 return ath79_misc_intc_of_init(node, parent);
168 }
169
170 IRQCHIP_DECLARE(ar7240_misc_intc, "qca,ar7240-misc-intc",
171 ar7240_misc_intc_of_init);
172
ath79_misc_irq_init(void __iomem * regs,int irq,int irq_base,bool is_ar71xx)173 void __init ath79_misc_irq_init(void __iomem *regs, int irq,
174 int irq_base, bool is_ar71xx)
175 {
176 struct irq_domain *domain;
177
178 if (is_ar71xx)
179 ath79_misc_irq_chip.irq_mask_ack = ar71xx_misc_irq_mask;
180 else
181 ath79_misc_irq_chip.irq_ack = ar724x_misc_irq_ack;
182
183 domain = irq_domain_add_legacy(NULL, ATH79_MISC_IRQ_COUNT,
184 irq_base, 0, &misc_irq_domain_ops, regs);
185 if (!domain)
186 panic("Failed to create MISC irqdomain");
187
188 ath79_misc_intc_domain_init(domain, irq);
189 }
190